1. Field of the Invention
The present invention relates to a cooling system for a plastic extrusion calibrating tool. More specifically, the present invention provides for a cooling system which allows for a greater equivalent cooling of a cooling fluid for a particular volume of cooling fluid to thereby provide for a more efficient cooling of a calibrating tool in an extrusion system.
2. Discription of the Prior Art
In the extrusion of plastic materials to a desired shape, the extruded material is passed through a calibrating tool. The calibrating tool has a configuration to provide for a desired shape for the extruded article. The calibrating tool generally includes a channel of a particular length so as to confine the extruded material within the length of the calibrating tool. This allows the extruded material to be cooled sufficiently so that when the extruded material leaves the calibrating tool, the extruded material maintains its desired shape. In order to insure that the extruded material is cooled sufficiently, calibrating tools may include the use of coolant which is circulated within the interior of the calibrating tool in order to draw off the heat from the extruded material as it passes down the length of the calibrating tool.
Prior art calibrating tools have suffered from not having a sufficient volume of circulation of coolant and not having a sufficient surface area for the path of the coolant within the calibrating tool so as to draw off as much heat as desired for a given length of the calibrating tool.